transom repair

[jeff akin]

Got old I/o boat that iam rebuilding on a budget. I've had some discussions about I/o conversion to outboard and nobody seems to like idea but cost dictates the conversion and like everything else I do i'll tinker till I get it right. Now to the point, I 've been following alot of threads on transom repair and it's very helpful but my question is this why are there no synthetic products to use instead of a wood core on transoms (not counting the seacast stuff for smaller boats) Could you not layer glass woven roven and mat to similar or greater thickness, Or aluminum sheet or some other panel style product?

 

[danond]

Re: transom repair

Seacast has nothing to do with application size. It will work as a wood replacement, along with Nidabond.

People tend to go wood because it's significantly cheaper and just as effective.

An all fiberglass transom would be very expensive and flexible. There has to be a hard, non-flexible structure in place to support an engine.

 

[proshadetree]

Re: transom repair

I dont know about flex of a 3 inch thick transom made out of fiberglass but the cost.I dont see fiberglass bonding to aluminum that well so delamination might be the issue.Cost is why plywood is back there.

 

[danond]

Re: transom repair

Yeah 3" thick probably wouldn't flex.

 

[jeff akin]

Re: transom repair

Thanks for the anwsers just thought i'd check on alternatives to wood but I guess the traditional methods are still the best. Just one more question I'm going to do the transom repair with resin instead of epoxy because of the amount of repair work I have to do and the cost associatied. I had planned on layering 3/4'' plywood with fiberglass mat to make a sandwich of three panels of 3/4" with two layers of mat in between and wrapping the thing with cloth before inserting into transom and bonding to original outer fiberglass layer (the one with gelcote) everyone talks on here of the peanut butter technique is it possible to make resin in to a peanut butter consistantcy with some type of filler without losing much strength or is it better to put mat against original glass and using it to bond to new plywood structure and pressing them together, any help appreciated thanks alot!

 

[haulnazz15]

Re: transom repair

Actually, I made my transom on my 76 20' I/O beefier than the original. The orignial used 2 sheets of 3/4" plywood across the entire back end, with an additional 3/4" added to the center section where the transom plate was. When I rebuilt the transom this past year with Seacast, I made the entire thing 2-1/4" all the way across. I guarantee you that seacast is twice as strong as the plywood original ever was. In addition, I don't have to worry about it ever rotting or flexing.

The downside is the cost, it ran about $900 to buy the materials. But it was going to cost 2K to pay somone to do it with plywood, and would have costed me $400+ to do it myself with plywood.

Also, going from I/O to outboard is probably going to be detrimental to performance and handling on your boat, depending on size. The outboard put the weight all on the back edge of the boat, further pushing the stern in the water, also having to deal with getting the height right and customizing everything that goes along with the outboard parts. Good luck to you though.

 

[jeff akin]

Re: transom repair

yeah I Know everybody on the site seems to hate idea of I/O conversions to outboard but the cost is the issue has well has safety (had some bad expierance with inboard gas engine (lots of facial air lost!!!) so I am going to be hard headed and do it anyway. The seacast is interesting if you had a outboard well type boat I could see the ease there as well as strength.Mine is kind off the same hull as the old 23c formula where the center is plywood and the rest of transom is fiberglass on sides of transom and the wood doesn't extend to top of transom where cap attaches. so it seems would be diffucult to pour Let me try to figure out how to post pictures.thanks

ps every picture I try to upload seems to be larger than allowed by site Have to see if teenage son can fix I'll try tommorrow thanks

 

[ezmobee]

Re: transom repair

If your determined to do the conversion then go for it. And document it well for all of us. I've heard it said on here for years that people who do this conversion typically aren't happy with the results but I don't think I've seen one done. Looking forward to your pics.

 

[haulnazz15]

Re: transom repair

If your bad experience with the inboards was due to fire, then something was wrong. If the blower wasn't being run to vent the fuel fumes, or you can a fuel leak turned into a fire it wasn't a safety issue, it was a issue of improper operation. Also, te cost of an outboard and related equipment will likely outweigh going with a reman'd I/O powerplant. Outboards are extremely expensive, especially when getting on with enough HP to push a 23' boat. You're gonna need a 250HP+, so get ready for a 6K+ outlay for he engine alone.

The transom I repaired is the same is you mentioned. Fiberglass skin on both sides of a plywood center, the transom-backing material stops a couple of inches from the upper cap. The SeaCast isn't as easy as pouring soup into a hole, more like shoving thick mud into a hole. Meanwhile, the Seacast is getting hot and the fiberglass fibers and material are tearing through your nitrile rubber gloves. It takes some work, but when it's done, you know it won't rot or leak unless something rips the entire back wall of the boat off.

 

[jeff akin]

Re: transom repair

haulnazz the boat had two exhaust blowers and I was only one in boat had brother back down ramp had checked bilge and readied boat on level ground. All blowers had been running for quite a while and the engine and fuel supply system had been replace properly, unknown to us, one of the wing tanks had been improperly repaired by previos owner with permatex sealant (of course not rated for fuel use, aluminum tank repair or anything related to his use of it) when boat was backed down ramp the raising of bow caused fuel to pour out of the fill neck of boat as boat setteled in water I fired the engine and it took about 45 seconds before the big kabboom. No matter how well the alt,starter or ignition system is sealed fuel and air combinitions will find ignition source. I realize that people operate boats with gas engines all the time and if maintainance is done properly there should not be a problem,but once was enough for me I'll stick to my diesel or at least an outboard I shudder to think what would have happened had my two and five year old been in boat. Plus I was coast guard for 8 years and never once has the guard purchased a boat with gas engine in boat because of the risk of fire. thanks for the info though.

 

[haulnazz15]

Re: transom repair

I understand your issue with it, but as you mentioned: it was due to an improper repair. I'm not sure that an outboard wouldn't have ignited the fumes just the same. The application that the Coast Guards use is a little different that a runabout, I don't think they avoid them because of fire issues.

 

[jeff akin]

Re: transom repair

Allright I'll concede that they are ok, but it'll never leave my thoughts and I will always hesitate when it comes to wife and kids. It'll cause me to worry more than enjoy so I have to choose different route, but I did check into mercruisers deal with cummins deisels and if I went to single 220 hp+- diesel purchase price for package would still run around 18,000. Best option but cannot swing cost. Don't want any more payments. But have wheel and dealed a little and managed to get triple engine floatation bracket from a scarab for 700.00 in good shape that will fit nicely on transom area I have. And currently have a pair of counter rotation 1990 johnson outboards (200HP) that were running takeoffs for under thousand. Not exactly age I wanted but price was right and worse case if this doesn't work not out a whole lot. If outboard or outboards (hav'nt decided) work well and I can balance hull properly than I wont feel to bad about buying a nicer outboard in a year or so.

 

[jeff akin]

Re: transom repair

Hey still curious can I make some type of peanut butter from resin instead of epoxy to bond my plywood, fiberglass sandwich that I will probably build on a sawhorse to the exterior fiberglass layer that I have left on boat. I'm almost ready to build it, I have transom 90% prepped and I'm looking for local fiberglass supply house here in orlando to buy bulk mat and woven roven and resin instead of the mail order thing. thanks again.

 

[haulnazz15]

Re: transom repair

I didn't know you already had the outboards, that does make it a bit more pheasible. I don't think you would want a diesel in a boat that small. Most don't offer diesels until you get close to the 30ft cruisers.

 

[jeff akin]

Re: transom repair

Mercruiser has new I/O program with cummins as partner and there selling I/O diesel packages that are supposed to be direct replacement for alpha one 260 type setups little high revving 4 cyl but they aint cheap and the local dealer says only 2 year limited warranty unlike outboard guys and there five year deals? nobody have any idea on using resin to make peanut butter instead of epoxy

 

[jeff akin]

Re: transom repair

Has anybody heard of vinylester resin, local fiberglass wholesaler say property and strength are comparable to epoxy, with exception that it has increased stiffness over epoxy. The price seems to be mid way between traditional resin and epoxy. The place recommends for high performance applications thanks again

 

[danond]

Re: transom repair

Epoxy is stronger than vinylester.

http://www.redrockstore.com/resin.htm

 

[jeff akin]

Re: transom repair

Danod finally got to check out your website pretty damn good and the boat didn't turn out half bad either.(haha) I can't even figure out what to do with all the pictures of mine I'm taking. All kidding aside the boat came out great! Got some great ideas from your site. I'm to the point of purchasing the wood and the glass just waiting on wife to give thumbs up on the money.(Can't say much when wife is working 2 jobs) Got hull sanded out and I'm going to add quite a bit of gusseting, to support the transom with bracket and 400 hp. Guess I'll have to tye it all to stringers and bottom of hull with ply and lots of glass probably will weigh quite a bit more when done thanks for the link to us composites there stuff is more attainable cost wise the west. Hopefully soon I can get son to post all the pictures thanks again for the help.

 

[danond]

Re: transom repair

Glad you're on your way. Open a photobucket.com account and upload the pictures there. Easy and works great when posting them to the forums. Good luck!

Thanks for the compliments on the website, by the way.

 

[jeff akin]

Re: transom repair

Hey I think this might work for the photos, Ill try to insert the link to photbucket. There is quite a few pictures of the boat just kinda uploaded all of them. thanks
http://s682.photobucket.com/albums/vv183/jeffakin/

Also was at home depot shopping for wood today, they are selling luan plywood that they claim to be water resistant, for 11 dollars a sheet its only about a 1/4 in size but seems stout for the thickness. If you layered the luan and chopped strand mat in alternating layers with epoxy for say 8 or 9 layers of wood would there be a net gain in strength for the many layers of glass and wood versus two layers of 3/4 inch and one layer between them of mat as always thanks for the ideas.